1. Field of the Invention
The present invention relates to casings for use with light-emitting units and a method of manufacturing the light-emitting units, and it particularly relates to a technology by which to form the light-emitting unit having a high performance capability of thermal emission.
2. Description of the Related Art
Conventionally, illuminators using light-emitting devices, such as LEDs (light emitting diodes), have been provided with some waterproofing arrangement to enable outdoor installation. Among such waterproofing methods, a technique for filling the casing, or enclosure, with transparent resin is known (see, for example, Reference (1) in the following Related Art List).
Related Art List
(1) Japanese Patent Application Laid-Open No. 2003-059335.
However, when such resin liquid is injected into the casing through a hole made therein, air bubbles tend to form in the liquid resin, which may deprive the material of necessary thermal conductivity. Furthermore, such air bubbles showing on the surface would give a poor appearance to the product and an impression of low product reliability. To remove the air bubbles, additional processes are required, thus making the manufacturing of the illuminator more complex and consequently raising the unit cost of the product.